my car has a bad knock in it and i was wondering if anyone had any suggestions. It is a very consistent knock but im not sure if its a valve or a main bearing.

 

It's hard to diagnose sound over the internet, but I can tell you valves don't knock.

 

Need a LOT more information before anyone can really help you. True knock's are generally not a good thing. You sure it is not a ping? Is your SES light on?

I long time ago I had a knock that sounded muffeld or far away. It turned out to be thrown rod caused by a spun bearing. Not saying that is your problem but many things can cause a knock. Be as specific as possible and maybe someone can help.

 

I had the same issue at 57,000 miles my car started knocking, and it get louder and higger rpms, so i took of the heads to check the rocker arms, maybe they came loose, I actually had piston slap........